In CDMA communication, the reception signal is multiplied by spreading code, and the correlation value is obtained after integrating the multiplication results.
In the circuit where it is necessary to carry out correlation detection in a small period of time comparing to a time corresponding to 1 chip (for example, DLL: Delay Locked Loop), there are problems that a circuit configuration becomes complicated, circuit scale becomes large, and power consumption increases with increasing of processing speed.
In addition, there is a case in which transmission side apparatus notifies reception side apparatus whether special processing are carried out or not using a special code. For example, in W-CDMA method applied to IMT2000, the transmission side apparatus notifies reception side apparatus whether STTD transmission diversity processing is carried out or not using synchronization code.
However, an appropriate correlation detection cannot be carried out in the reception side under bad reception environment, and reception side apparatus cannot determine whether the reception signal includes a signal subjected to transmission diversity processing or not.